An octagonal shape has eight sides and eight angles. It is a type of polygon, which is a flat shape with straight sides. The angles in a regular octagon are all equal, measuring 135 degrees each. Common examples of octagonal shapes include stop signs and certain types of tiles. In geometry, the term "octagon" comes from the Greek words "okto," meaning eight, and "gonia," meaning angle. Octagons can be found in various designs and structures, such as buildings and parks, and they are often used in art and architecture to create visually appealing patterns.